Objective To study the morphological characteristics of femurs of adult human and 11 kinds of adult animals fromcattle, horses, pigs, goats, sheep, dogs, cats, rabbits, geese, ducks, chickens, and to establish an effective species identification method among various species. Methods The 4 cmmid-dia-physeal segment of the femur fromadult human (older than 20 years old) at autopsy w as obtained. Addi-tionally, the 4 cmones from11 kinds of adult animals w ere obtained. After decalcification, all femurs w ere made into slices, and then w ere observed by optical microscope. The 25 indexes w ere selected and analyzed by step discriminant analysis according to differences betw een human and mammal, human and poultry, and human and 11 kinds of animals. Results The histological structure of bone mineral density of middle part of femur had obvious characteristics among the species. And the morphology and number of osteon show ed the trend of obvious biological evolution. There w ere 11 indexes w ith significant differ-ences betw een human and 11 kinds of animals to establish some mathematical models to discriminate all species. The correct discrimination rate w as 96.3% betw een human and mammal. The correct discrimina-tion rate w as up to 100% betw een human and poultry, and w as 89.4% among human, mammal and poultry. Conclusion The mathematical models have good correct discrimination rate among human and the other animals, w hich could be applied in the practical species identification cases.